Clean the surface thoroughly with a wire brush to remove any loose or broken mortar and dirt from the surface.

If you see white, powdery deposits (efflorescence) it must be removed. Treat efflorescence by washing with a solution of DRYLOK® Etch (liquid or powdered formula) or muriatic acid according to manufacturer’s directions, rinse and allow to dry. Since efflorescence occurs naturally, we cannot warrant against recurring efflorescence. If efflorescence is not present, proceed to Step 2

WARNING!  If you scrape, sand or remove old paint, you may release lead dust.  LEAD IS TOXIC. Contact the National Lead Information Hotline    at 1-800-424-LEAD or log on to


Patch Cracks and Holes

Fill all holes and cracks with DRYLOK® Fast Plug®. Wet down and back chisel the area, to the shape of an inverted “V” this allows the patch to lock into the surface and cure properly.

Fast Plug® sets up rapidly, so only mix enough patch to be used in 3 to 5 minutes.


Seal The Floor And Wall Joint.

When patching, don’t forget the area where the floor and wall meet.  Often, when concrete floors cure, they shrink and pull away from the wall, allowing a space for water to enter.  Fill this area as described above.


Apply DRYLOK® To Masonry Walls

Stir DRYLOK® thoroughly before and during application. Apply using a 3/4 in. nap roller, DRYLOK® Brush or good quality nylon bristle brush. If rolled, back-brush the first coat to fill any pinholes in the masonry.  DRYLOK® must be worked into the pores of the masonry, making sure to fill all pores and pinholes. Proper coverage is important for waterproofing. 1 gallon covers a 8 ft. x 10 ft. area. A minimum of two coats is required to assure warranted waterproofing. Allow the DRYLOK® to dry between coats following the label instructions.
Important:  After the second coat dries, inspect entire wall surface for pinholes in the waterproof coating.  Any areas with pinholes should be painted with an additional coat to ensure waterproofing results.